Toyota Repair: 2000 Sienna Vibration in higher speeds., cv joints, cv joint

Question
I just had $800 in brakes, rotors, etc on my sienna .
before this job, i had no vibration issues.
When my van exceeds 95km/hour it starts to shake and gets worse at higher speeds, and again, it was fine BEFORE brake job.
Took it back to brake shop (Speedy) and they were good, but could not figure it out
Balanced all the tires, did not work, rotated the tires, did not work.
The mechanic thought there was some play in front left drive shaft or axle.
Could it be the CV joints or both the axle and the CV joint, but how would this be caused by changin brake pads ?
Any insight would be helpfull
thks
Don

Answer
Is it in the wheel?, Then its in the front.
If you feel it in the vehicle but not the wheel its in the rear,

Get a second opinion.

They must have done something. It needs to be seen by someone competant.
I personally dont have much faith in SPEEDY.

Mike